Acute Toxicity and Gastroprotection Studies of a New Schiff Base Derived Copper (II) Complex against Ethanol-Induced Acute Gastric Lesions in Rats

Background

Copper is an essential element in various metabolisms. The investigation was carried out to evaluate acute gastroprotective effects of the Copper (II) complex against ethanol-induced superficial hemorrhagic mucosal lesions in rats.

Methodology/Principal Findings

Rats were divided into 7 groups. Groups 1 and 2 were orally administered with Tween 20 (10% v/v). Group 3 was orally administered with 20 mg/kg omeprazole (10% Tween 20). Groups 4–7 received 10, 20, 40, and 80 mg/kg of the complex (10% Tween 20), respectively. Tween 20 (10% v/v) was given orally to group 1 and absolute ethanol was given orally to groups 2–7, respectively. Rats were sacrificed after 1 h. Group 2 exhibited severe superficial hemorrhagic mucosal lesions. Gastric wall mucus was significantly preserved by the pre-treatment complex. The results showed a significant increase in glutathione (GSH), superoxide dismutase (SOD), nitric oxide (NO), and Prostaglandin E2 (PGE₂) activities and a decrease in malondialdehyde (MDA) level. Histology showed marked reduction of hemorrhagic mucosal lesions in groups 4–7. Immunohistochemical staining showed up-regulation of Hsp70 and down-regulation of Bax proteins. PAS staining of groups 4–7 showed intense stain uptake of gastric mucosa. The acute toxicity revealed the non-toxic nature of the compound.

Conclusions/Significance

The gastroprotective effect of the Copper (II) complex may possibly be due to preservation of gastric wall mucus; increase in PGE₂ synthesis; GSH, SOD, and NO up-regulation of Hsp70 protein; decrease in MDA level; and down-regulation of Bax protein.     

Molecular screening of Streptomyces isolates for antifungal activity and family 19 chitinase enzymes

Thirty soil-isolates of Streptomyces were analyzed to determine their antagonism against plant-pathogenic fungi including Fusarium oxysporum, Pythium aristosporum, Colletotrichum gossypii, and Rhizoctonia solani. Seven isolates showed antifungal activity against one or more strain of the tested fungi. Based on the 16S rDNA sequence analysis, these isolates were identified as Streptomyces tendae (YH3), S. griseus (YH8), S. variabilis (YH21), S. endus (YH24), S. violaceusniger (YH27A), S. endus (YH27B), and S. griseus (YH27C). The identity percentages ranged from 98 to 100%. Although some isolates belonged to the same species, there were many differences in their cultural and morphological characteristics. Six isolates out of seven showed chitinase activity according to a chitinolytic activity test and on colloidal chitin agar plates. Based on the conserved regions among the family 19 chitinase genes of Streptomyces sp. two primers were used for detection of the chitinase (chiC) gene in the six isolates. A DNA fragment of 1.4 kb was observed only for the isolates YH8, YH27A, and YH27C. In conclusion, six Streptomyces strains with potential chitinolytic activity were identified from the local environment in Taif City, Saudi Arabia. Of these isolates, three belong to family 19 chitinases. To our knowledge, this is the first reported presence of a chiC gene in S. violaceusniger YH27A.     

Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission

ABSTRACT: BACKGROUND: Artemisinin-based combination therapy (ACT) for treating malaria has activity against immature gametocytes. In theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can infect vector mosquitoes. However, this has never been verified at a population level in a setting with intense transmission, where chronically infectious asymptomatic carriers are common and cured patients are rapidly and repeatedly re-infected. METHODS: From 2001 to 2004, malaria vector densities were monitored using light traps in three Tanzanian districts. Mosquitoes were dissected to determine parous and oocyst rates. Plasmodium falciparum sporozoite rates were determined by ELISA. Sulphadoxinepyrimethamine (SP) monotherapy was used for treatment of uncomplicated malaria in the contiguous districts of Kilombero and Ulanga throughout this period. In Rufiji district, the standard drug was changed to artesunate co-administered with SP (AS + SP) in March 2003. The effects of this change in case management on malaria parasite infection in the vectors were analysed. RESULTS: Plasmodium falciparum entomological inoculation rates exceeded 300 infective bites per person per year at both sites over the whole period. The introduction of AS + SP in Rufiji was associated with increased oocyst prevalence (OR [95%CI] = 3.9 [2.9-5.3], p < 0.001), but had no consistent effect on sporozoite prevalence (OR [95%CI] = 0.9 [0.7-1.2], p = 0.5). The estimated infectiousness of the human population in Rufiji was very low prior to the change in drug policy. Emergence rates and parous rates of the vectors varied substantially throughout the study period, which affected estimates of infectiousness. The latter consequently cannot be explained by the change in drug policy. CONCLUSIONS: In high perennial transmission settings, only a small proportion of infections in humans are symptomatic or treated, so case management with ACT may have little impact on overall infectiousness of the human population. Variations in infection levels in vectors largely depend on the age distribution of the mosquito population. Benefits of ACT in suppressing transmission are more likely to be evident where transmission is already low or effective vector control is widely implemented.     

Cancer cells are highly susceptible to accumulation of templated insertions linked to MMBIR

Microhomology-mediated break-induced replication (MMBIR) is a DNA repair pathway initiated by polymerase template switching at microhomology, which can produce templated insertions that initiate chromosomal rearrangements leading to neurological and metabolic diseases, and promote complex genomic rearrangements (CGRs) found in cancer. Yet, how often templated insertions accumulate from processes like MMBIR in genomes is poorly understood due to difficulty in directly identifying these events by whole genome sequencing (WGS). Here, by using our newly developed MMBSearch software, we directly detect such templated insertions (MMB-TIs) in human genomes and report substantial differences in frequency and complexity of MMB-TI events between normal and cancer cells. Through analysis of 71 cancer genomes from The Cancer Genome Atlas (TCGA), we observed that MMB-TIs readily accumulate de novo across several cancer types, with particularly high accumulation in some breast and lung cancers. By contrast, MMB-TIs appear only as germline variants in normal human fibroblast cells, and do not accumulate as de novo somatic mutations. Finally, we performed WGS on a lung adenocarcinoma patient case and confirmed MMB-TI-initiated chromosome fusions that disrupted potential tumor suppressors and induced chromothripsis-like CGRs. Based on our findings we propose that MMB-TIs represent a trigger for widespread genomic instability and tumor evolution.     

小檗色素的提取及其理化性质研究

研究了不同溶剂对小檗色素的提取效果,以及不同pH、不同金属离子、氧化剂和还原剂对该色素稳定性的影响。结果表明,小檗色素在40％的乙醇溶液及水中的溶解效果最好;在酸性条件下色素较稳定;铁离子对其有增色作用;氧化剂、还原剂对色素稳定性均有影响,其中以还原剂影响较大。通过对小檗色素理化性质的研究,表明该色素在化妆品、食品、染料、饮料等工业领域有很大的应用前景。     

Efficacy of African weaver ant,Oecophylla longinoda (Hymenoptera: Formicidae) in reducing losses due to frugivorous fruit flies (Diptera: Tephritidae) in smallholder mango production systems in Eastern Tanzania

Fruit flies (Diptera: Tephritidae) are dipteran insects that cause high losses of fruits and vegetables in the tropical and subtropical regions of the world. As quarantine pests, fruit flies affect export markets because trade regulations hamper export of fruits from areas with occurrence of fruit flies. We compared the effectiveness of Oecophylla longinoda with the insecticide; imidacloprid for the control of Bactrocera dorsalis in a 6-year-old orchard of mango cultivar ‘Apple’. Mango samples at different developmental stages were collected between September and November in 2012 and between November 2013 and January 2014 at a three-week interval between sampling dates. Every fruit was cultured in a separate individual plastic container containing approximately 500?g sieved sterilised sand. Three weeks later, larvae and pupae were sieved from sand and counted. In both years, significantly higher (P?<?.0001) incidences and infestation rates were recorded in the control plots when compared to the trees protected with insecticides and O. longinoda. Incidences and infestation rates did not differ significantly (P?>?.05) between insecticide and weaver ants protected fruits, implying that O. longinoda was as effective as imidacloprid in suppressing the population of fruit flies. Peak fruit fly incidences and infestation rates coincided with the ripening stage of mango fruits. Our results have shown that the incidences and infestation rates on incubated mango fruits were lowest in the O. longinoda and the imidacloprid protected trees. Thus, O. longinoda is an effective bio-control agent that could be exploited to serve as a vital Integrated Pest Management component on mango orchards.     

新疆天山西部山脉森林生态系统地衣群落结构的初步研究

 根据多年的研究资料并采用聚类分析方法对分布在天山西部山脉的地衣群落结构进行了研究。结果表明,分布在该地区的地衣种类形成了6种群落:1) 土星猫耳衣（Leptogium saturninum)＋矮石蕊(Cladonia humilis)＋兰灰蜈蚣衣（Physcia caesia）群落;2）黑穗石蕊（Cladonia amaurocr     

Correlation of -475 IL-2 Promoter Gene Polymorphisms and the Levels of Serum IL-2 on the Risk of Multiple Sclerosis

Background:The aim of present study is to asset the IL-2 promoter gene (SNP -475) as a candidate gene for multiple sclerosis (MS) susceptibility.Methods:This study included 70 patients with relapsing – remitting multiple sclerosis (RRMS) and 50 healthy controls. Following the extraction of genomic DNA from peripheral blood, frequency of genotypes and alleles of SNP -475 was calculated using Restriction fragment length polymorphism-polymer chain reaction (RFLP-PCR) and then the results were analyzed statistically.Results:The results revealed the unusual ratio for the heterozygous (AT) was 1.6972 indicating that heterozygous patients were at higher risk of multiple sclerosis than wild homozygous (AA), and homomutant (TT). The results show protective role for - 475 IL-2 promoter among individuals with multiple sclerosis, (O.R: 0.4872; C.I. 95%: 0.1617- 1.4680) and (O.R: 0.9275; C.I. 95%: 0.2476 - 3.4745) for both AA and TT genotypes, respectively.Conclusion:Our results showed that in this population of Iraqi patients, the AT genotype / A allele of -475 IL-2 promoter gene SNP may include attributed factors for MS predisposition.Key Words: IL-2, Multiple sclerosis, PCR-RFLP SNP